Just when you think they've tried everything, NASA comes up with some new science experiment to be performed in orbit around the planet.

As you see in the video above, the latest plan involves twin astronauts Mark and Scott Kelly. The agency will send one into space, keep another on Earth, and compare their biologies, using the Earth-bound twin as a control.

It sounds simultaneously logical and a little bit weird, but not remotely as weird as these six examples of experiments conducted in space.

Spider-nauts

So imagine: You’re an astronaut on a space station, doing a really stressful job while hurtling in a claustrophobic metal tube through the most hostile environment known to mankind, when the radio crackles.

“Hey guys,” Mission Control says. “We’re just gonna send you up some spiders. Yes, spiders, those things with the legs and the webs and the bloodsucking. Cool?”

We’re sure the conversation didn’t really go like that (NASA science experiments are scrupulously planned), but we hope the crew aboard Skylab wasn’t finicky about arachnids when two cross spiders, Arabella and Anita, were blasted up into space for a series of student-suggested experiments in 1973:

“Space spiders” sounds horrible, but the science was legit: They wanted to see if the eight-legged passengers could spin webs in zero-G like they do on Earth. In Arabella and Anita’s case, they had trouble doing so. Eventually they succeeded (before dying of dehydration), but the webs’ thickness was uneven.

Apparently “spiders in space” crops up on a lot of NASA science wish-lists, because that duo weren’t remotely the only ones to go into space. A 2008 batch, apparently better cared for than the 1970s pioneers, started out poorly, but soon turned out to be masters of spinning space webs.

In 2011, a pair of golden orb spiders, Gladys and Esmerelda, were monitored in special compartments as they spun webs to capture fruit flies that had been sent up with them. NASA partnered with educators to allow schools to monitor the experiments, with around 130,000 students signed up.

And it seems they don’t even need webs. At the suggestion of a student in Egypt, a pair of jumping spiders, Cleopatra and Nefertiti, were sent up in 2012, and it turns out they had no trouble changing their tactics in zero-g.

Space Spider - 'Cleopatra' lives! Eating the last of her fruit flies, waiting for a ride back to Earth on Dragon-1 pic.twitter.com/exhXg9WZ

We don’t know the fate of Cleopatra, but it seems her companion, Nefertiti, survived the trip back to Earth and adjusted fine to a gravity environment, before dying a couple months shy of the species’ average one-year lifespan.

And the spider space race continues. In 2012, yet another batch of spidernauts blasted off for the International Space Station, this time aboard a Dragon space capsule. Only this time, they hadn’t even hatched from their eggs yet, as scientists (and, yes, still more students, who suggested the experiment) want to see if spiders born in space behave differently from their earthbound brethren.

Fish, and the art of swimming in space

Continuing in the vein of picking a random animal and shooting it into space to see what it does: That same 1973 flight aboard Skylab included a pair of mummichogs, to see how fish can swim in zero gravity.

The short answer: Badly, at least at first. The fish kept “diving,” and ended up spinning round and round in small circles (you can sort of see what that looked like in the first seconds of the grainy old documentary footage below).

However, by week three, they’d more or less figured it out, orienting themselves by turning their backs to available light sources as a substitute for gravity. Fish hatched from eggs sent along on the same mission had no trouble.

That was just the first known experiment. Others would follow, and even recently two crucial tests took place that are key to figuring out how humans adapt to space in the long-term.

First, Japanese researchers sent a special habitat to the International Space Station, then sent up several medaka fish, which are ideal for space-science: They’re translucent, so their bones and organs can be monitored without surgery, and they breed often, so researchers can study generations born on Earth AND in space.

Specifically, they collected data on radiation levels, bone development, muscular atrophy and other stiff challenges faced by astronauts who have to spend large amounts of time in space.

The environment and the experiments were hard on the fish – it seems most of them died.

Not quite fish-related, but still in the aquatic life category, researchers actually studied the development of jellyfish in space recently.

A creature with no bones should have no trouble in zero-g, but whether they’re born in space or on Earth, all jellyfish develop a series of crystals, surrounded by cells, which help them tell up from down. And it turned out jellyfish that grew up in space had serious problems adapting to life on Earth.

That’s big news for humans. We have our own natural gravity sensors, based in our inner ears, and the jellyfish’s hassles are a good indicator of what our own children could face if they are born in space and then have to adjust to a gravity environment when taken to Earth.

Space brew

NASA is very much a dry operation, with no booze allowed on the International Space Station (with good reason). After a series of allegations of astronauts turning up drunk for launch on two occasions, the agency even revised its rules to ban drinking alcohol less than 12 hours prior to a spaceflight in 2007.

But as the frontiers of space science advanced to cover almost all aspects of the natural world, including nutrition, the subject of space brew has come up on more than one occasion.

For starters, NASA originally planned to produce a kind of sherry suitable for consumption by astronauts aboard Skylab in the 1970s, stored in special packages and limited to four ounces every four days.

That plan didn’t last long. One whiff of the sherry aboard a zero-g test flight aboard NASA’s “vomit comet” aircraft sent passengers and crew scrambling for the barf-bags. It seems space sherry mixed with lingering smells of past weak-belly “accidents” aboard the plane was a bad combination to someone whose stomach was already in free fall. As well, the public backlash to the idea of serious scientists having alcohol in space helped persuade officials to can the project (Russian cosmonauts aboard Mir were apparently allowed a supply of cognac).

But the idea of drinkable alcohol in space has remained alluring, attracting its share of space dollars for researching how it affects the human body in space.

A grad student in Colorado once sent a brewing kit along on a space shuttle flight, which did produce a small quantity of beer. But by the time our relentless pioneer of science sampled the brew, its taste was ruined by the chemicals used in testing.

Even drinking beer in space poses it own challenges. With no gravity, you couldn’t get a head on it, as the carbon dioxide wouldn’t bubble to the surface, and with no gravity, a side-effect of having it in your belly has been diplomatically described as “wet burps.”

Regular beer kegs and pumps wouldn’t work right either, but luckily Dutch scientists developed a special mechanism that would allow beer to be pumped out of a tap (it gathers in tennis-ball sized globs of black gold. The researchers recommend a straw).

Some breweries are looking past NASA with an eye on future space tourists: